Methods for generating soil maps and application prescriptions

ABSTRACT

Methods are provided for generating a prescription map for the application of crop inputs. In one method, the user draws a boundary on a map within a user interface and the system identifies relevant soil data and generates a soil map overlay and legend for changing the application prescription for various soils and soil conditions. In another method, the user instead drives a field boundary which is recorded on a planter monitor using a global positioning receiver, and the system generates a soil map and legend for changing the application prescription.

BENEFIT CLAIM

This application claims the benefit as a Continuation of applicationSer. No. 13/978,339, filed Jul. 3, 2013, which claims the benefit as aU.S. National phase application of International Appln.PCT/US/2011/068219, filed Dec. 30, 2011, which claims the benefit ofProvisional Appln. 61/429,635, filed Jan. 4, 2011, the entire contentsof each of which is hereby incorporated by reference as if fully setforth herein, under 35 U.S.C. § 119(e) and 35 U.S.C. § 120. Theapplicant(s) hereby rescind any disclaimer of claim scope in the parentapplication(s) or the prosecution history thereof and advise the USPTOthat the claims in this application may be broader than any claim in theparent application(s).

BACKGROUND

When planting corn or other crops, a key decision is the spacing betweeneach seed. Decreasing spacing increases the overall population (i.e.,the number of seeds per acre), which increases the number of crop plantsin a given area but causes the plants to increasingly compete forsunlight and soil resources, reducing the productivity per plant.

Modern planters such as that disclosed in U.S. Pat. No. 5,956,255 areable to vary the population while planting and to use a “prescriptionmap” prescribing a population (and thus seed spacing) for each locationin the field. In planters like that disclosed in the '255 patent, anelectronic planter monitor receives the planter's current location inthe field from a GPS receiver and consults the prescription map todetermine the currently desired population while planting.

When creating a prescription map to optimize yield, it is desirable toset different populations for different soil types and conditions. Forexample, the optimal population is likely higher with more productivesoils. Thus in many cases it is desirable to increase the populationwhen planting in more productive soils and decrease the population whenplanting in less productive soils.

In order to identify soil types and productivity in a given field,services such as the Soil Data Mart maintained by the United StatesDepartment of Agriculture (“USDA”) provide soil data maps such as soiltype maps. The soil data maps comprise sets of polygons, each of whichconstitutes the border around each differentiated soil type orcondition. The vertices of the polygons correspond to a latitude andlongitude. Each polygon is associated with a data set, which may includethe soil type and the estimated yield for various crops.

In FIG. 9A, a tractor 920 is schematically illustrated drawing avariable rate application implement 926 (e.g., a planter) through afield along a direction of travel indicated by an arrow 928. A soil map900 comprises a polygon 902 having soil type 2, with the area outsidepolygon 902 having soil type 1. The soil map 900 may be converted to aprescription map requiring a seed population 2 inside the polygon 902and a seed population 1 outside the polygon 902. As the planter 926moves across the field as shown in FIG. 9A, it will plant at population1 until crossing the boundary into polygon 902, at which point it plantsat population 2 until exiting polygon 902. Since the planter 926generally includes multiple row units arranged transverse to thedirection of travel, the row units are preferably controlled separatelysuch that, e.g., if the rightmost row unit enters polygon 902 before theleftmost row unit, the rightmost row unit will begin planting atpopulation 2 first. As illustrated in FIG. 9B, the prescription map mayalso be converted to a raster image 950 instructing the planter to plantat certain populations in discrete areas or “rasters” of the same size.

Several commercially available software programs assist the user increating planting prescription maps using soil maps and other field datamaps. For example, using one commercially available farm managementprogram, the user obtains an image file containing relevant aerial orsatellite imagery and obtains a “shape file” comprising soil polygonsfor a geographical subdivision (e.g., a county) of interest from a soildata server. Typical soil data servers will place the user's soil maprequests in a queue; when the user's request is reached, the soil dataserver searches for the requested boundary, creates a correspondingshape file and alerts the user that the shape file download isavailable. Once the user has obtained the soil map and aerial imagery,such programs display both images side by side and allows the user toselect corresponding points comprising a field boundary on both images.The program then uses the corresponding points to “clip” the polygons inthe soil map to the field boundary and displays the clipped soil maplaid over the aerial image. Some farm management software programsadditionally allow the user to import a field boundary driven andrecorded using a global positioning receiver. Once transferred to thesoftware, the GPS boundary may be used to clip aerial imagery to thefield boundary.

Commercially available systems described require multiple complex stepsto appropriately match field boundaries, aerial imagery and soil dataimagery. Such systems also require a dedicated software program on theuser's computer to perform the various operations involved. Due to theseinconveniences many users choose to employ an agronomy service togenerate prescriptions. Thus there is a need for a simpler, faster andmore intuitive method of generating prescription maps.

DESCRIPTION OF THE DRAWINGS

FIG. 1A schematically illustrates an embodiment of a system forgenerating soil maps and prescriptions.

FIG. 1B illustrates an embodiment of a process for generating a soil mapand prescription.

FIG. 2A illustrates an embodiment of a user interface enabling a user tonavigate to a field.

FIG. 2B illustrates an embodiment of a user interface enabling a user todraw a field boundary.

FIG. 2C-2D illustrate embodiments of a user interface displaying a soilmap and related soil data and enabling a user to enter a seed populationprescription.

FIG. 2E illustrates an embodiment of a user interface allowing a user toexport seed population prescriptions and soil maps.

FIG. 3 illustrates an embodiment of a planter monitor user interfacedisplaying a soil map and prescription and allowing a user to modify aprescription.

FIG. 4 schematically illustrates another embodiment of a system forgenerating a soil map and prescription.

FIG. 5 schematically illustrates another embodiment of a process forgenerating a soil map and prescription.

FIG. 6 illustrates an embodiment of a planter monitor user interfaceenabling a user to record a field boundary.

FIG. 7 illustrates a preferred an embodiment of a process for generatinga soil map.

FIG. 8A illustrates an embodiment of a user interface enabling a user toadd an external shape to a soil map.

FIG. 8B illustrates an embodiment of a user interface enabling a user tocreate a prescription based on a soil map and external shapes.

FIG. 9A illustrates a prior art soil and prescription map.

FIG. 9B illustrates a prior art raster image.

DESCRIPTION Prescription Generation Systems

Referring now to the drawings, wherein like reference numerals designateidentical or corresponding parts throughout the several views, FIG. 1Aschematically illustrates a preferred prescription system 100. Theprescription system 100 preferably includes a user computer 120, aplanter monitor 150, a data transfer device 180, a global positioningreceiver 190, a user interface 110, a map service 130, a soil dataserver 140, a system server 160, and a system database 170.

The planter monitor 150 is in electrical communication with the globalpositioning receiver 190. The planter monitor 150 is in datacommunication with the user computer 120 preferably through the datatransfer device 180 such as a USB or flash drive. The user computer 120is in data communication with the user interface 110 through an Internetconnection 50. The user interface is preferably accessible using anInternet browser on the user computer 120, but may be accessible using adedicated program stored on the user computer 120. The map service 130and system server 160 provide data to the user interface 110. The systemserver 160 is in electrical communication with the system database 170.The system server 160 is in data communication with the soil data server140 through an Internet connection 50.

It should be appreciated that although a preferred embodiment isdescribed as using Internet connections and data storage devices, thetype of data transfer method or device between each component is notessential to the prescription system 100. That is, any suitable device,system or method may be used to transfer data between components or toput the components in communication with one another. In addition, itwill be appreciated that the functions of the user computer 120 andplanter monitor 150 may be combined into a single device, and the datastored and retrieved on the various servers may also be stored on asingle device.

Prescription Generation Methods

A preferred prescription generation process 200 for using theprescription system 100 to generate a seed population prescription isillustrated in FIG. 1B. The user preferably logs into user interface 110at step 210 by providing identifying information such as a username andpassword as is known in the art. At step 220, the user interface 110displays a map from a map service 130, and enables the user to navigateto the field of interest by providing location information through theuser interface 110 or by manipulating the map. At step 225, the userinterface preferably enables the user to enter unique identifyinginformation for the field into the user interface 110. At step 230, theuser interface enables the user to draw a boundary within the field onthe map. At step 240, the system server 160 accesses soil data from thesoil data server 140 and generates a soil map illustrating soil typeswithin the boundary drawn by the user. The system server 160 alsoprovides soil data related to each soil type to the user interface 110,which preferably generates and displays a table summarizing the soildata at step 245. The user interface then allows the user to enter adesired crop input application parameter, e.g., seed population, foreach soil type at step 250, resulting in a prescription for the entirefield which may be stored in the system database 170. At step 252, theuser interface enables the user to export the prescription to a mobiledevice, e.g., the planter monitor 150, using the data transfer device180. During planting, the planter monitor 150 determines its location inthe field using the global positioning receiver 190 as is known in theart and sets the population rate associated with the correspondinglocation on the prescription map.

The prescription generation process 200 is illustrated further in FIGS.2A-2E with reference to the user interface 110. As illustrated FIG. 2A,the user interface 110 displays a map 260 obtained from a map service130 such as Google Maps or TerraServer. The map 260 preferably comprisesa navigable aerial image map including a layer of aerial or satelliteimages and may additionally include layers identifying street names andother reference information. The area displayed on map 260 may bemanipulated by the user by dragging the map, using a pan control 263 ora zoom control 262 as is known in the art. The field selection dialog280 includes a “New Field” tab 281. Using the New Field tab 281, theuser may enter the location (e.g., city and state or latitude andlongitude) of the field of interest in location field 282, whichpreferably results in a request to the map service 130 to display thedesired location. The user may also enter data into a “Client” field 283and a “Farm Name” field 284, and may further enter data into a “FieldName” field 285 such that the new field is associated with a specificclient and farm for later access by the user. The user may also enterdata into an expected “Tillable Acres” field 286 of the field. Once theuser selects the “Draw Boundary” link 287, the system server 160preferably saves data entered on the New Field tab 281 to the systemdatabase and opens a boundary selection dialog 288 illustrated in FIG.2B.

As illustrated in FIG. 2B, a boundary selection dialog 288 instructs theuser to draw a boundary around the field of interest. The user uses acursor 294 to select each vertex 292 of the field, and the userinterface 110 displays a resulting boundary 290 connecting the vertices292. Once the user returns to and selects the first vertex 292-1, afield creation dialog 296 allowing the user to create the field orcancel creation of the boundary 290. While the user draws the boundary290 by selecting additional vertices (e.g., 292-1 through 292-6 asillustrated), boundary selection dialog 288 preferably displays thelatitude and longitude of the cursor 294. The prescription system 100preferably obtains the geographic locations (e.g., in latitude andlongitude or in GPS coordinates) corresponding to each vertex of theboundary 290 from the map service 130 and stores the geographiclocations in the memory of the computer 120 or in the system database170. When the user has created a complete boundary 290, the boundaryselection dialog 288 preferably displays a calculated field size,preferably displayed in calculated acreage (539 in FIG. 2C) forcomparison with the expected tillable acres entered in field 286. Thecalculated acreage may be determined using the distances between thegeographic locations corresponding to vertices 292 as is known in theart.

When the user chooses to create the field using the field creationdialog 296, the prescription system 100 preferably generates a soil map560 corresponding to the extents of the boundary 290 as illustrated inFIG. 2C. As discussed in further detail later herein, the system server160 obtains soil type polygons and associated soil data intersectingwith or entirely within the field boundary 290 from a soil data server140 such as that maintained by the Natural Resources ConservationService (“NRCS”). The soil map 560 comprises the portions of the soiltype polygons within the boundary 290. In FIG. 2C, the soil map polygons561, 562, and 563 have been clipped to the boundary 290.

At the stage illustrated in FIG. 2C, the user may confirm the accurateplacement of the boundary by adjusting the transparency of the soil map560 using transparency adjuster 549 or by comparing the field calculatedacres to the estimated tillable acres.

Continuing to refer to FIG. 2C, the user interface 110 preferablydisplays a table in a “Soil Type Rx” tab 565 in a “Create Prescription”dialog 550 displaying data associated with each soil map polygon. In theexample of FIG. 2C, three management zones 561, 562 and 563 are shownwhich are associated with respective management zone rows 551, 552, and553 in the Create Prescription dialog 550 of the Soil Type Rx tab 565.As discussed further below with respect to FIG. 7, it should beappreciated that the soil map polygons 561-1 and 561-2 were part of thesame soil polygon obtained from the soil data server that were splitinto two separate soil map polygons by the boundary 290, such that bothsoil map polygons 561-1 and 561-2 correspond to the single managementzone row 551. As illustrated, the correspondence of polygons andmanagement zones is preferably indicated by hatching or coloring on theuser interface 110. The data displayed for each management zone row mayinclude estimated yield data 555, acreage data 556, and soil type data557. It should be appreciated that multiple categories of soil data maybe available for each management zone row; the system preferably selectsthe most relevant data to display based on a predetermined preferenceschedule. Each management zone row 551-553 also preferably includes adefault population value in population fields 554. In the illustratedexample, the default population is set at zero, but in other embodimentsthe default population could be set at a non-zero value such as 30,000seeds per acre.

As illustrated in FIG. 2D, the user interface 110 also allows the userto create a prescription for the field by entering a desired populationin the “Population” field 554 (e.g., in seeds per acre) for each soilmap polygon by entering a numerical value or by using adjustment arrows541 to adjust the population (e.g., in increments of 500 seeds per acre)associated with each Population field 554. Once the user has entered atleast one population, the Create Prescription dialog 550 preferablydisplays the average population in the “Average Population” field 542representing the calculated average population across the field. Theuser may also enter data in an estimated “Double Plant” percentage field543 representing the estimated percentage of the field that will have tobe passed over multiple times. The prescription creation dialogpreferably displays estimated seed units in an “Estimated Seed Units”field 544 required for the field, having a value which the system server160 calculates using an appropriate equation, e.g.:

${{{Seed}\mspace{14mu} {Units}} = \frac{({Acreage})\left( {{Average}\mspace{14mu} {Population}} \right)\left( {1 + {{Double}\mspace{14mu} {Plant}\mspace{14mu} {Fraction}}} \right)}{\left( {{Seeds}\mspace{14mu} {per}\mspace{14mu} {Unit}} \right)}},$

Where:

-   -   “Acreage” is either the calculated acreage or the user-entered        tillable acreage;    -   “Average Population” is the calculated average population;    -   “Double Plant Fraction” is the double plant percentage expressed        as a fraction;    -   “Seeds per Unit” is an estimated number of seeds per storage        unit (e.g., 80,000 seeds per bag).

Under some circumstances, it is desirable to create multipleprescriptions for a single field. As an example, the user may desire toset a prescription for each hybrid or type of hybrid that may be plantedin the field of interest. Under such circumstances, the user may createa new prescription for the same field using drop-down “Attribute” menu558. In the illustrated embodiment the Attribute is generically named“Population.” When the user creates a new prescription, it is createdunder a user-entered attribute name (e.g., a hybrid type such as “flex”or “semi-flex”), the populations entered in Population fields 554preferably return to the default value and the user may enter and savenew desired populations entered in the Population fields 554 for eachmanagement zone row 551, 552 and 553. There are several applications inwhich it is useful to set multiple prescriptions to the same field. Inthe simplest application, the user may not know which hybrid will beused for the field while creating prescriptions and the user may choosethe appropriate prescription in the field once the hybrid has beenselected. In a more complex application, each row unit or section of rowunits on the planter that is individually controlled may be controlledby a different prescription. Thus the user may plant multiple hybrids inthe same field by providing different hybrids to various row units andcontrol each row unit using the appropriate prescription. It should beappreciated that prescriptions may be created for other attributes usingthe system described herein; for example, a prescription may be createdfor a given hybrid with and without nitrogen application.

Once the user has entered the prescription and selected the “Save” link559, the user interface 110 preferably displays a prescription “Export”dialog 590 as illustrated in FIG. 2E. The selection fields 591 allow theuser to search only fields corresponding to the client and faint ofinterest. The row corresponding to each field (e.g., “North Field” inFIG. 2E) includes a textual export status 594 and an export status icon592 indicating whether the field has been exported. When the userselects the “Export Fields” link 596, the soil map data is exported fromthe user computer 120 to the data transfer device 180.

Turning to FIG. 3, the user may transfer the soil map data from the datatransfer device 180 to the planter monitor 150. The planter monitor 150may comprise a planter monitor including features similar to thosedisclosed in Applicant's co-pending application Ser. No. 13/292,384, thedisclosure of which is incorporated by reference herein in its entirety,and preferably includes a graphical user interface 300 such as a touchscreen display as well as a central processing unit and a memory. Theplanter monitor 150 preferably displays a boundary 290 and soil mappolygons 561-1, 561-2, 562 and 563. Prescription windows 311, 312, and313 preferably display the current population, soil type, and other data(e.g., a crop productivity index) corresponding to each management zone.The planter monitor 150 preferably displays data corresponding to theentire boundary 290 such as “Map Acres” field 352 and “AveragePopulation” field 354. The planter monitor 150 preferably allows theuser to modify the prescription in the field using, e.g. a touch screeninterface. In the illustrated embodiment of FIG. 3, the user may usearrows 320 to navigate between prescription windows 311-313 and may useprescription adjustment arrows 330 to adjust the population for a givenboundary in increments of, e.g., 500 seeds per acre. The user may alsouse the “Select All Soil Types” button 325 to select all soil types forsimultaneous adjustment using the prescription adjustment arrows 330.Once the population has been altered the user may select the “Enter”button 360 to save the altered prescription, which may be exported tothe data transfer device 180 and imported to the user computer 120.

A preferred method of generating the soil map 260 is illustrated in FIG.7. The steps generally indicated at 750 are preferably performed by theInternet browser or dedicated program on the user computer; the stepsgenerally indicated at 760 are preferably performed by the system server160. At step 710, the user interface 110 activates boundary drawingtools allowing the user to draw a field boundary 290 over a map 260 asdescribed above. At step 715, the Internet browser or dedicated programon user computer 120 preferably converts the resulting boundary vertices292 into a document in standard format readable by the soil data server,such as a standardized markup language document, e.g., an extensiblemarkup language (“XML”) document. At step 720, a request is sent to thesoil data server 140 in order to obtain the soil map polygons thatintersect the boundary 290 defined by the boundary vertices 292. At step725, a request is sent to the soil data server 140 also for soil dataassociated with the polygons obtained at step 720. The requests sent atsteps 720,725 are preferably a standardized format, e.g., a markuplanguage, readable by the soil data server. The process just describedwith respect to steps 715, 720 and 725 is faster than requesting anentire shape file corresponding to a geographical or politicalsubdivision (e.g., a county) because such a shape file includesirrelevant soil polygons.

At step 730, the system server 160 clips the soil map polygons to theboundary 290. This operation may be performed by using an appropriateapplication programming interface such as JTS Topology Suite, availablefrom Vivid Solutions in Victoria, British Columbia, to create polygonsthat represent the topological or geometric union between the boundary290 and each original soil polygon. It should be appreciated that theoriginal soil map polygons returned by the soil data server 140 mayextend for miles beyond the boundary 290; as such, it is advantageous toperform clipping operations on the system server 160 rather thantransferring the original polygons to the user computer 120.Transferring the potentially large original polygons to the usercomputer 120 and using a potentially less powerful processor on usercomputer 120 to perform the clipping operations requires longerprocessing times and likely requires a dedicated program on the usercomputer 120.

At step 732, the system server 160 associates each clipped soil mappolygon with a “management zone.” When first obtained from the soil dataserver 140, each original polygon is typically associated with a key orother unique identifier, which key is also associated with each articleof data pertaining to that polygon. However, a single polygon can beconverted into multiple polygons after being clipped to a boundary (seepolygons 561-1 and 561-2 in FIG. 2C). In such cases, the key associatedwith the original polygon must be associated with each resultingpolygon. Each polygon associated with the equivalent unique identifier(e.g., the same unique key) is preferably identified with the samemanagement zone. Thus in FIG. 2C, polygons 561-1 and 561-2 are part ofthe same management zone.

At step 735, the system server 160 preferably attaches the data (e.g.,soil type and corn yield) associated with each unique key to thecorresponding management zone.

At step 740, the system server 160 preferably converts the data returnedfrom the soil data server to a format usable by a web applicationplatform such as Adobe Flash, e.g., an XML document. At step 745, theInternet browser or dedicated program on user computer 120 receives theXML document and uses it to create application objects such as thecontent of management zone rows 551-553 discussed above with referenceto FIG. 2C. It should be appreciated that each management zone row551-553 corresponds to a management zone, and the data illustrated ineach management zone row 551-553 (with the exception of the user-enteredprescription and the calculated acreage of the management zone) is thedata from the soil data server 140 associated with the same key.

At step 747, the user interface 110 sends the latitude and longitude ofthe multiple vector points corresponding to the boundaries of theclipped polygons to the map service 130, along with instructions for thecolor of the polygons. The vector points and instructions are preferablycompatible with the application program interface provided by the mapservice 130. At step 748, the map service 130 generates a map overlayrepresenting the clipped soil polygons which is positioned and sized tomatch the boundary 290 on the map 260. It should be appreciated that themap service 130 includes a remote map server as well as an applicationprogram interface provided by the map server that runs on the usercomputer 120; as such, the creation of the map overlay may be carriedout either on the remote map server or on the user computer 120. Itshould also be appreciated that as the user subsequently drags the map260 or uses the pan control 263 or the zoom control 262, the map service130 updates the map overlay such that the soil polygons remainpositioned and sized to match the location and scale of boundary 290.

Prescription Generation Methods—Adding External Shapes

In creating a population prescription, it is sometimes desirable to setprescriptions based not only on varying soil types but on other externalfactors such as irrigation. Thus the user interface 110 preferablyallows the user to add external shapes such as irrigation pivots to theprescription map. As illustrated in FIG. 8A, the “Create Prescription”dialog 550 may include “Shapes” tab 810 for adding shapes includinglinks 812 and 814 which launch drawing tools to draw full and partialpivots, respectively. When, e.g., the Draw Full Pivot link 812 isselected, an instructive dialog 816 is displayed instructing the user touse the cursor 294 to draw an irrigation boundary. In the illustratedembodiment, the user first uses the cursor 294 to place a center point817. As the cursor 294 is moved away from the center point 817, the userinterface 110 displays the circumference of the pivot and theinstructive dialog 816 displays the calculated area under the pivot. Itshould be appreciated that the map layer 260 may assist the user inselecting the appropriate pivot radius, as the user is often able tovisually discern the irrigated area from the aerial or satelliteimagery. Once the user has selected the appropriate location for thepivot circumference, the user interface 110 creates a shape 870representing the pivot area.

The step of adding a pivot area shape 870 or other external shape may beperformed before or after the user interface 110 displays the soilpolygons within the boundary 290. In the example illustrated in FIG. 8A,the pivot area shape 870 has been added to a soil map including soilpolygons 861 and 862. It will be appreciated that both soil polygonshave portions within the pivot area and outside the pivot area. Asillustrated in FIG. 8B, a Soil Type Rx tab 565 of the CreatePrescription dialog 550 preferably allows a user to set separatepopulation prescriptions for the portions of each soil polygon that areinside and outside the pivot area using an inside pivot prescriptionfield 856 and an outside pivot prescription field 854.

Monitor-Based Prescription Generation Systems and Methods

Depending on circumstances and available technology, users may prefer tocreate prescriptions entirely on the planter monitor 150. For thesepurposes, a distinct prescription system 400 for creating a prescriptionis illustrated schematically in FIG. 4. The prescription system 400includes user computer 120, soil map database 175, data transfer device180, planter monitor 150, and global positioning receiver 190.

Turning to FIG. 5, a process 500 is illustrated for using theprescription system 400 to generate a prescription. At step 512, a soilmap for a relevant area is imported to the planter monitor 150,preferably using the data transfer device 180. The planter monitor 150is preferably configured to control the rate of application input, e.g.,the seed population rate. It should be appreciated that in the process500, it is necessary to obtain soil data for an area larger than theplanned field boundary since the exact boundary is not known when thesoil data is imported to the planter monitor 150. Thus the user mayobtain soil data for an entire county or other geographical subdivisionusing user computer 120. Such bulk data may be downloaded in shape fileformat from a soil map database 175 such as that maintained by the NRCS.

At step 510, the user drives the boundary of the field of interest whilethe planter monitor 150 records a series of global positioning verticesreported by the global positioning receiver 190, thus recording a filedboundary 290. A preferred display 600 for guiding the user through thisprocess is illustrated in FIG. 6. An icon 620 represents the location ofthe global positioning receiver 190. When the user selects the “RecordField Boundary” button 632, the status bar 612 indicates that theplanter monitor 150 is recording the boundary 290. A “start of boundary”icon 622 represents the first recorded vertex of the boundary 290. Theuser may pause recording at any time by selecting the “Pause” button 634and may preferably select the Pause button again to resume recording theboundary 290 after navigating back to the last recorded location. Theindicator 610 reports the distance between the boundary being recordedand the physical location of the global positioning receiver 190, alongwith an arrow indicating the direction (preferably from the perspectiveof the operator while driving the tractor) in which the boundary isoffset from the global positioning receiver. Once the user has returnedsufficiently close to the beginning of boundary 290, the user selectsthe “End Field Boundary” button 630 to store the boundary. The boundary290 may be saved under a unique filename using the “Name” field 640.

Returning to FIG. 5, at step 513 the planter monitor 150 generates aboundary file (preferably an XML file) representing the field boundary290 from the recorded global positioning vertices. At step 514, theplanter monitor 150 identifies relevant soil map polygons intersectingthe field boundary. At step 516, the planter monitor 150 generatesmanagement zones; as discussed elsewhere herein, each management zonecorresponds to the portion or portions of each relevant polygon withinthe field boundary. At step 518, the planter monitor 150 displays acontrol map comprising the set of management zones. The control mappreferably includes a default application parameter (e.g., seedpopulation) associated with each management zone At step 520, theplanter monitor 150 enables the user to modify the default applicationparameter using an interface such as graphical user interface 300 asillustrated in FIG. 3. Once the user has created the prescription, thecontrol map may be used to control input application and may be saved tothe data transfer device 180.

Although the foregoing description describes methods of creating seedplanting prescriptions, it should be appreciated that the same methodscould be used to generate spatially dependant crop input prescriptionsfor any variable rate crop input such as fertilizer. Moreover, althoughthe foregoing description describes methods of using a soil map tocreate a prescription, the same or similar methods could be used togenerate a prescription based on any map of field data. For example, theuser could import a yield map containing polygons or rasters associatedwith various yields from a prior year and prescribe application ratesfor each such polygon or raster.

Additionally, although the methods described herein involve a usermanually creating a prescription once presented with field data, it iswell known in the art to create prescriptions using formulae whoseinputs include field data. Thus, for example, the system could allow theuser to specify a formula (or provide a formula) for converting cornyield into a population prescription. According to such a method, in theillustration of FIG. 2C the prescription system 100 would generatepopulations for population fields 554 for each soil map polygon 561, 562and 563 using an equation that was a function of, e.g., corn yield andfactors associated with each soil type and stored in a lookup table.

The foregoing description is presented to enable one of ordinary skillin the art to make and use the invention and is provided in the contextof a patent application and its requirements. Various modifications tothe preferred embodiment of the apparatus, and the general principlesand features of the system and methods described herein will be readilyapparent to those of skill in the art. Thus, the present invention isnot to be limited to the embodiments of the apparatus, system andmethods described above and illustrated in the drawing figures, but isto be accorded the widest scope consistent with the spirit and scope ofthe appended claims.

What is claimed is:
 1. A method comprising: through a user interface,receiving user input defining a boundary of a field of interest by ageographic location data; accessing a soil data map associated with saidfield of interest based on said geographic location data, said soil datamap identifying soil types of said field of interest; receiving userinput selecting a particular seed population for a particular soil typeof the identified soil types of said field of interest through said userinterface; identifying a plurality of locations within said field whichcomprise the particular soil type; in response to receiving said userinput selecting the particular seed population, selecting the particularseed population for each of the plurality of locations identified ascomprising the particular soil type and storing a seed plantingprescription comprising the particular seed population for each of theplurality of locations comprising the particular soil type.
 2. Themethod of claim 1, further comprising: receiving user input defining aboundary of said field of interest; displaying a portion of said soildata map as defined by said boundary, said soil data map comprising soiltype polygons each identifying a soil type, wherein only portions ofsaid soil type polygons within said defined boundary are displayed. 3.The method of claim 1, wherein accessing said soil data map comprisessending a request to a soil data server in a markup language readable bythe soil data server.
 4. The method of claim 2, wherein said boundarycomprises multiple vector points, and wherein accessing said soil datamap comprises sending said vector points to a soil data map service andreceiving a map overlay of soil type polygons.
 5. The method of claim 4,wherein displaying a portion of said soil data map as defined by saidboundary comprises determining a geometric union between said definedboundary and said soil type polygons.
 6. One or more non-transitorycomputer-readable media storing instructions which, when executed by oneor more processors, cause performance of: through a user interface,receiving user input defining a boundary of a field of interest by ageographic location data; accessing a soil data map associated with saidfield of interest based on said geographic location data, said soil datamap identifying soil types of said field of interest; receiving userinput selecting a particular seed population for a particular soil typeof the identified soil types of said field of interest through said userinterface; identifying a plurality of locations within said field whichcomprise the particular soil type; in response to receiving said userinput selecting the particular seed population, selecting the particularseed population for each of the plurality of locations identified ascomprising the particular soil type and storing a seed plantingprescription comprising the particular seed population for each of theplurality of locations comprising the particular soil type.
 7. The oneor more non-transitory computer-readable of claim 6, wherein theinstructions, when executed by one or more processors: receiving userinput defining a boundary of said field of interest; displaying aportion of said soil data map as defined by said boundary, said soildata map comprising soil type polygons each identifying a soil type,wherein only portions of said soil type polygons within said definedboundary are displayed.
 8. The one or more non-transitorycomputer-readable of claim 6, wherein accessing said soil data mapcomprises sending a request to a soil data server in a markup languagereadable by the soil data server.
 9. The one or more non-transitorycomputer-readable of claim 7, wherein said boundary comprises multiplevector points, and wherein accessing said soil data map comprisessending said vector points to a soil data map service and receiving amap overlay of soil type polygons.
 10. The one or more non-transitorycomputer-readable of claim 9, wherein displaying a portion of said soildata map as defined by said boundary comprises determining a geometricunion between said defined boundary and said soil type polygons.